If you can get some old 25 pair phone cable out of a building, it makes perfect hookup wire for use in the breadboards, and many other things. However... solid

If you can get some old 25 pair phone cable out of a building, it makes perfect hookup wire for use in the breadboards, and many other things. However... solid wire tends to get brittle and break after repeated flexing, never use it for permanent connections that undergo any movement.